1. Field of the Invention
The present invention relates to an image forming apparatus, a power supplying method, and computer-readable storage medium.
2. Description of the Related Art
Conventionally, there is a known image forming apparatus that, when printing is suspended, stops power supply from a commercial power source but continuously operates a circuit for detecting a printing execution instruction by supplying power to the circuit from a power source separate from the commercial power source. For example, Japanese Patent Application Laid-open No. H7-199739 discloses an image forming apparatus provided with a starting circuit that operates to detect a printing execution instruction by receiving power from a battery. In the image forming apparatus disclosed in Japanese Patent Application Laid-open No. H7-199739, during a sleep mode in which printing is suspended, a relay interposed between a commercial power source and a power supply unit that supplies power from the commercial power source is switched to the off-state to stop power supply from the commercial power source, but the starting circuit is continuously operated. In this state, when the starting circuit detects a printing execution instruction, the relay is switched to the on-state. Accordingly, power supply from the commercial power source is resumed, so that an image forming unit that forms an image on a medium is activated to perform printing.
However, in the technology disclosed in Japanese Patent Application Laid-open No. H7-199739, while the relay is operated by using power charged in the battery, if the discharge efficiency (the discharge loss) of the battery is taken into account, it is necessary to charge the battery with a much greater amount of power than the amount of power needed to operate the relay. Therefore, it is difficult to sufficiently reduce the power consumption of the image forming apparatus.
Therefore, there is a need for an image forming apparatus capable of reducing the power consumption.